In the manufacture of plastic objects comprising several raw materials, the essential factor is to mix the materials as well as possible before injection into the mold. This ensures that the two different raw materials form an homogeneous injection molding material.
A generic method is known from the DE-GM 74 14 436. Multi-component plastics, i.e., polyurethanes, are processed by conducting individual components to a mixing chamber via feed lines. At the same time, a mixing chamber is energized. As a result, the mixed plastic also begins to exit from the exit opening of the mixing chamber into the mold cavity.